481 
THE GEOLOGY AND THE OIL AND GAS PROSPECTS OF THE SOVIET 
CONTINENTAL SHELF 
As may be seen from the following survey, Soviet hydrocarbon 
prospects, although not all proven, are substantial. The Soviet Union 
has a coastline approximately 37,000 kilometers long with a continen- 
tal shelf which covers an area of about 6 million square kilometers 
to a depth of 200 meters. The shelf includes different geologic ele- 
ments ranging from ancient platforms to structural and sedimentary 
basins and folded belts. It is divided into three large regions: the 
continental shelves of the remnant seas in southern Russia (such as 
the Caspian Sea, the Black Sea, and the Sea of Azov) which are 
connected with the Mediterranean geosynclinal zone; the continental 
shelf of the Arctic seas and the Arctic basin; and the continental 
shelf of the Pacific Far East mobile zone. (see map.) 
Geological knowledge of these shelf areas is rather scanty except 
for the Caspian Sea shelves which are well known. The Russian con- 
tinental shelves are expected by Soviet geologists to be an important 
source of new oil and gas production. Oil and gas potential, however, 
differs in different parts of the shelves, but in the Caspian Sea 
prospects for large hydrocarbon reserves are certain. 
SOUTHERN U:S.S.R. 
In the southern region of the Soviet Union there are large, geologi- 
cally active, crustal depressions which contain great thicknesses of 
sedimentary rock (20 kilometers in the Caspian Sea area and 10 
to 12 kilometers in the Black Sea). The presence of these thick 
sedimentary rock sections and the discovery of large accumulations 
of oil and gas both offshore and under the adjoining lands indicate 
excellent hydrocarbon potential for the continental shelves of southern 
U.S.S.R. and especially for the Caspian Sea shelf. The Caspian Sea 
is at present undergoing extensive offshore drilling and exploitation. 
It is the world’s largest interior body of water, with an area of 430,000 
square kilometers. Approximately 60 percent of this area is 200 meters 
or less in depth. 
Geologically, the Caspian depression is composed of diverse struc- 
tural elements. In the northern Caspian, a salt dome area is developed 
on the Russian Precambrian platform (see Figure 1 for geologic time 
scale). Thick upper Paleozoic and Mesozoic rocks overlie the plat- 
form. On land this stratigraphic section is productive of oil and gas 
and gives every indication of being productive beneath the Caspian 
Sea. Even the strata that are older than the salt layers (pre-Permian) 
are expected to yield oil and gas.” 
The northern and middle parts of the Caspian depression are struc- 
turally complex with a cover of Mesozoic and Cenozoic sediments. 
The Jurassic and Cretaceous sedimentary rocks of this complex struc- 
tural element offer the greatest promise of oil and gas.* 
The most favorable section of the Caspian Sea for hydrocarbons, 
however, is the Apsheron-Balkhan zone, a sill that separates the 
2 Eremenko, N. A., Malovitskiy, Ya. P., Gramberg, I. S., and Lebedev, L. I. Geologic Structure and 
Oil and Gas Prospects of the U.S.S.R. Continental Shelf. American Association of Petroleum Geolo- 
gists Bulletin, v. 57, n. 2, February 1973, p. 239. 
3 Ibid. : 
